ref: ed41adf84beca7e87d191ac8e98cec12de56ee16
dir: /src/doom/m_random.c/
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005-2014 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// DESCRIPTION:
// Random number LUT.
//
//
// M_Random
// Returns a 0-255 number
//
static const unsigned char rndtable[256] = {
0, 8, 109, 220, 222, 241, 149, 107, 75, 248, 254, 140, 16, 66 ,
74, 21, 211, 47, 80, 242, 154, 27, 205, 128, 161, 89, 77, 36 ,
95, 110, 85, 48, 212, 140, 211, 249, 22, 79, 200, 50, 28, 188 ,
52, 140, 202, 120, 68, 145, 62, 70, 184, 190, 91, 197, 152, 224 ,
149, 104, 25, 178, 252, 182, 202, 182, 141, 197, 4, 81, 181, 242 ,
145, 42, 39, 227, 156, 198, 225, 193, 219, 93, 122, 175, 249, 0 ,
175, 143, 70, 239, 46, 246, 163, 53, 163, 109, 168, 135, 2, 235 ,
25, 92, 20, 145, 138, 77, 69, 166, 78, 176, 173, 212, 166, 113 ,
94, 161, 41, 50, 239, 49, 111, 164, 70, 60, 2, 37, 171, 75 ,
136, 156, 11, 56, 42, 146, 138, 229, 73, 146, 77, 61, 98, 196 ,
135, 106, 63, 197, 195, 86, 96, 203, 113, 101, 170, 247, 181, 113 ,
80, 250, 108, 7, 255, 237, 129, 226, 79, 107, 112, 166, 103, 241 ,
24, 223, 239, 120, 198, 58, 60, 82, 128, 3, 184, 66, 143, 224 ,
145, 224, 81, 206, 163, 45, 63, 90, 168, 114, 59, 33, 159, 95 ,
28, 139, 123, 98, 125, 196, 15, 70, 194, 253, 54, 14, 109, 226 ,
71, 17, 161, 93, 186, 87, 244, 138, 20, 52, 123, 251, 26, 36 ,
17, 46, 52, 231, 232, 76, 31, 221, 84, 37, 216, 165, 212, 106 ,
197, 242, 98, 43, 39, 175, 254, 145, 190, 84, 118, 222, 187, 136 ,
120, 163, 236, 249
};
int rndindex = 0;
int prndindex = 0;
// Which one is deterministic?
int P_Random (void)
{
prndindex = (prndindex+1)&0xff;
return rndtable[prndindex];
}
int M_Random (void)
{
rndindex = (rndindex+1)&0xff;
return rndtable[rndindex];
}
void M_ClearRandom (void)
{
rndindex = prndindex = 0;
}
// inspired by the same routine in Eternity, thanks haleyjd
int P_SubRandom (void)
{
int r = P_Random();
return r - P_Random();
}